Supported catalysts containing one or more metals from the group consisting of palladium, platinum, silver and gold have already been known for some time. Catalysts containing palladium or platinum and gold are preferably used in the synthesis of vinyl acetate from a reaction mixture of ethylene, oxygen and acetic acid. Various production methods for such supported catalysts are already known. Supported catalysts containing palladium and platinum, palladium or platinum and silver or gold, or palladium, silver and gold are likewise used in the hydrogenation of hydrocarbons, in particular the selective hydrogenation of polyunsaturated hydrocarbon compounds. Catalysts containing silver and/or gold are preferably used in the oxidation of alcohols to ketones/aldehydes/carboxylic acids. Thus, for example, precursor compounds which contain the corresponding metals are applied, dissolved preferably in an aqueous solution, to the surface of a support body. The support body containing the corresponding precursor compounds is then usually calcined under oxidic conditions in a high-temperature oven, wherein the metal-containing precursor compounds are converted into the metal oxides. The support bodies which contain the corresponding metal oxides are then subjected to reduction to the elemental metals in a separate unit. The fact that this method is carried out in two stages in separate units makes it laborious and cost-intensive. In addition, the starting materials are usually chloride-containing precursor compounds, which as a rule are very stable and therefore require high temperatures for decomposition to the metal oxides before they can be converted into the elemental metals by reduction.
It was therefore desirable to provide a method that is more cost-effective and more energy-saving than previously known methods, without the occurrence of significant losses of selectivity and activity during the reaction catalyzed by the catalyst.